Furniture Connector Dimensions Explained

Furniture Connector Dimensions Explained: Cam Diameter, Cam Height, Bolt Length and Drilling Distance

Furniture connector dimensions directly affect drilling, assembly and joint performance.

A buyer may request a “15 mm cam connector,” assuming that all 15 mm cams are interchangeable. However, cam diameter is only one part of the specification.

Two connectors with the same diameter may have different:

Cam heights
Internal locking profiles
Bolt-head requirements
Engagement positions
Drilling depths
Edge distances
Tightening directions
Compatible panel thicknesses

Selecting a connector by appearance or diameter alone can result in loose joints, incomplete tightening, damaged panels and production delays.

This guide explains the main furniture connector dimensions and the information manufacturers should confirm before production.

Quick Answer

The most important furniture connector dimensions are:

Cam diameter
Cam height
Cam-hole diameter
Cam-hole depth
Cam center distance from the panel edge
Connecting-bolt total length
Bolt working length
Bolt thread diameter and length
Bolt-head and neck dimensions
Bolt-hole diameter and depth
Alignment-dowel diameter and length
Distance between connector holes
Compatible panel thickness

A complete connector specification should define the matched cam, bolt, dowel and drilling pattern—not only one nominal dimension.

1. What Does “15 mm Cam” Mean?

A 15 mm cam normally refers to the nominal outside diameter of the cam housing or the corresponding drilling family.

It does not describe:

Cam height
Internal profile
Bolt size
Bolt length
Drilling depth
Engagement range
Edge distance
Panel thickness
Material
Surface finish

Therefore, the following description is incomplete:

15 mm zinc-alloy furniture cam

A more useful specification would include:

15 mm cam diameter, specified cam height, matching bolt reference, drilling dimensions, panel thickness and required material or finish.

The exact hole size and permitted tolerance should always come from the supplier’s approved drawing.

2. Cam Diameter

Cam diameter is usually shown as D, ØD or with a diameter symbol on the drawing.

It refers to the outside diameter of the circular cam body.

Why Cam Diameter Matters

Cam diameter affects:

Required drilling diameter
Amount of panel material removed
Available internal locking space
Compatibility with existing machinery
Distance from the panel edge
Panel thickness requirements

Common Mistake

A buyer measures an existing cam at approximately 15 mm and orders another 15 mm cam without checking its other dimensions.

The replacement may enter the hole but still fail to work because its internal profile or height is different.

What to Confirm

Nominal cam diameter
Actual permitted diameter range
Required hole diameter
Hole tolerance
Suitable panel material
Minimum suitable panel thickness
Cam insertion method

Do not automatically assume the drilled hole must equal the measured cam diameter in every system. Follow the connector drawing.

3. Cam Height

Cam height is the vertical dimension of the cam body.

It may also be described as:

Cam thickness
Housing height
Body height
Fitting height

Why Cam Height Matters

Cam height affects:

Required hole depth
Bolt engagement position
Remaining material below the hole
Cam stability inside the panel
Suitability for a particular panel thickness

Two cams can have the same 15 mm diameter but different heights.

If the wrong height is used, the cam may:

Sit above the panel surface
Sit too deeply in the hole
Miss the bolt head
Engage only part of the bolt
Damage the panel
Fail to pull the joint closed

What to Confirm

The specification should state both dimensions:

Cam diameter × cam height

For example, a product listed as D15 × H11.6 mm has a nominal diameter of 15 mm and a listed height of 11.6 mm.

This still does not confirm bolt compatibility; the matching bolt and drilling drawing must also be checked.

4. Cam-Hole Diameter

The cam-hole diameter is the diameter of the circular hole drilled into the panel face.

It must allow the cam to be installed while keeping it correctly positioned.

If the Hole Is Too Small

The cam may not enter
The panel surface may chip
Excessive insertion force may deform the cam
The hole may crack near the panel edge

If the Hole Is Too Large

The cam may move
Its alignment with the bolt may change
The cam may rotate unevenly
The surrounding panel may provide insufficient support

Production Controls

Furniture manufacturers should monitor:

Drill-bit diameter
Tool wear
CNC machine calibration
Hole roundness
Chipping around the hole
Panel density
Dimensional consistency between batches

Measure finished holes in actual panels, not only the cutting tool.

5. Cam-Hole Depth

Cam-hole depth determines how the cam sits inside the panel.

It is not automatically identical to the cam height. The correct relationship depends on the connector design and installation method.

If the Hole Is Too Shallow

The cam may:

Project above the surface
Fail to align with the bolt
Interfere with the adjoining panel
Become damaged during tightening

If the Hole Is Too Deep

The cam may:

Sit below the intended position
Lose correct bolt engagement
Move inside the hole
Leave insufficient panel material below it

What to Check

Cam height
Required drilling depth
Panel thickness
Remaining material beneath the hole
Bolt centerline
Whether the cam should be flush, recessed or positioned differently

Use drilling depth stops or controlled CNC programs during production.

6. Cam Center Distance From the Panel Edge

One of the most important dimensions is the distance between:

The panel edge
The centerline of the cam hole

This may be called:

Cam center distance
Edge-to-center distance
Drilling distance
Setback
Boring position

There is no single value suitable for all furniture connectors.

Why It Matters

The center distance determines whether the connecting bolt enters the cam at the correct position.

If the cam is drilled too close to or too far from the edge:

The bolt may miss the cam
The cam may engage only part of the bolt head
Panels may not close completely
The cam may break
The bolt may bend
The furniture joint may remain loose

Important Measuring Detail

Confirm whether the drawing shows:

Edge to hole center
Edge to hole wall
Edge to bolt centerline
Finished edge or unfinished board edge

These are different measurements.

7. Connecting-Bolt Total Length

Bolt total length is usually measured from one defined end of the bolt to the other, but the reference method may differ according to the bolt-head design.

The drawing should clearly show the measurement points.

Total Length Does Not Equal Working Length

A bolt may contain:

Threaded section
Unthreaded body
Stop collar
Neck
Engagement head

Only part of its total length may remain exposed after installation.

Therefore, two bolts with the same total length can produce different installed positions.

What to Confirm

Total length
Thread length
Unthreaded length
Installed depth
Exposed or working length
Head position after installation
Required panel thickness

8. Bolt Working Length

Bolt working length is the dimension that controls the position of the bolt head relative to the panel surface or joint line.

It may be more important for cam engagement than the total bolt length.

If the Working Length Is Too Short

The head may not enter the cam correctly
The cam may rotate without catching the bolt
The joint may remain loose

If the Working Length Is Too Long

The panels may not close
A visible gap may remain
The bolt may contact the wrong part of the cam
Excessive tightening force may damage the hardware

The installed position should be measured during the first production trial.

9. Bolt Thread Diameter and Length

The threaded section secures the bolt to the furniture panel or a separate insert.

Important thread specifications include:

Major diameter
Thread length
Thread form
Pitch where applicable
Installation-hole diameter
Installation method
Compatible insert or sleeve

A bolt intended for direct installation into particleboard may differ from one designed for:

Plastic expansion sleeves
Metal threaded inserts
Machine-threaded components
Solid wood
MDF
Plywood

A similar-looking thread is not necessarily interchangeable.

10. Bolt-Head and Neck Dimensions

The cam does not normally grip the bolt thread. It engages the bolt head or neck.

Therefore, the following dimensions are critical:

Head diameter
Head thickness
Neck diameter
Neck length
Distance from the head to the panel surface

If the head is too large, it may not enter the cam correctly.

If it is too small, the cam may not hold it securely.

If the neck is in the wrong position, the cam may reach its rotation limit without pulling the panels together.

The cam and bolt should always be approved as a matched combination.

11. Bolt-Hole Diameter and Depth

The bolt installation hole depends on the type of bolt.

Possible systems include:

Direct-screw bolts
Expansion bolts
Bolts with plastic sleeves
Machine-thread bolts
Bolts installed into metal inserts

Each system requires a different drilling specification.

If the Pilot Hole Is Too Small

Installation torque may become excessive
The board may split
The bolt may bend
The driver recess may become damaged

If the Pilot Hole Is Too Large

The thread may not hold
The bolt may rotate
The installed depth may change
The bolt may pull out

The correct pilot-hole diameter must be confirmed using the actual panel material because MDF, particleboard, plywood and solid wood behave differently.

12. Alignment-Dowel Dimensions

A 3-in-1 connector system commonly includes a separate alignment dowel.

Important dowel dimensions include:

Diameter
Total length
Insertion depth in each panel
Hole diameter
Hole depth
Distance from the cam
Distance from the panel edge

Why Dowel Dimensions Matter

A dowel that is too loose may not align the panels.

A dowel that is too tight may:

Make assembly difficult
Split the panel edge
Prevent the joint from closing
Damage the dowel hole

The two corresponding dowel holes must also align accurately.

13. Distance Between the Cam and Dowel

When a cam-and-bolt system is combined with an alignment dowel, the distance between the two connector centerlines becomes part of the drilling pattern.

Incorrect spacing can cause:

Misaligned panel edges
Difficult assembly
Twisted joints
Dowels that cannot enter their holes
Bolts that miss the cam
Stress around the drilled holes

The spacing must be measured from the same reference edge on both panels.

Do not drill the cam and dowel independently without checking their relationship.

14. Panel Thickness

Panel thickness influences almost every furniture connector dimension.

It affects:

Cam-hole depth
Remaining material below the cam
Bolt position
Edge distance
Dowel depth
Connector selection
Risk of panel breakout

A connector suitable for one panel thickness may not be suitable for a thinner panel.

Important Difference

Nominal and actual panel thickness may differ.

A panel sold under one nominal thickness may vary slightly because of:

Manufacturing tolerance
Surface coating
Lamination
Sanding
Material batch

Measure the actual production board before approving the drilling program.

15. Why Two 15 mm Cams May Not Be Interchangeable

Two cams with the same diameter may differ in:

Specification	Cam A	Cam B
Diameter	Same	Same
Height	May differ	May differ
Internal profile	One geometry	Another geometry
Compatible bolt	Bolt A	Bolt B
Tightening direction	May differ	May differ
Engagement range	May differ	May differ
Hole depth	May differ	May differ
Center distance	May differ	May differ
Panel application	May differ	May differ

The cam may physically fit inside the hole but fail during assembly.

This is why purchasing should be based on an approved connector set, drawing or reference sample—not diameter alone.

16. How to Read a Furniture Connector Drawing

A useful technical drawing should include several views.

Cam Drawing

Look for:

Outside diameter
Height
Driver recess
Directional mark
Internal engagement profile
Material
Finish

Bolt Drawing

Look for:

Total length
Thread diameter
Thread length
Body diameter
Neck length
Head dimensions
Driver type
Installation depth

Drilling Drawing

Look for:

Panel thickness
Cam-hole diameter
Cam-hole depth
Edge-to-center distance
Bolt-hole diameter
Bolt-hole depth
Dowel dimensions
Hole spacing
Drilling direction

Drawing Units

Confirm whether dimensions are stated in:

Millimetres
Inches
Both measurement systems

Never assume an unmarked drawing uses the expected unit.

17. Example of a Complete Connector Specification

The following is an illustrative format rather than a universal connector size:

Furniture cam connector set for specified panel thickness; cam diameter and height according to approved drawing; matching connecting bolt with defined total length, thread specification, head geometry and installed working length; alignment dowel where required; drilling pattern according to approved drawing; component ratio and packing quantity stated separately.

A purchasing specification may also reference:

Approved sample number
Product code
Drawing revision
Furniture model
Panel material
Surface finish
Packing method

Using an approved sample together with a controlled drawing reduces misunderstandings.

18. How to Measure an Existing Connector

When replacing an unknown connector, measure more than its diameter.

Measure the Cam

Outside diameter
Overall height
Internal opening
Driver recess
Directional features

Measure the Bolt

Total length
Thread diameter
Thread length
Neck diameter
Neck length
Head diameter
Head thickness

Measure the Panel

Actual panel thickness
Cam-hole diameter
Cam-hole depth
Edge-to-center distance
Bolt-hole diameter
Distance between additional holes

Use suitable measuring tools. Photographs alone are normally insufficient for identifying a compatible connector.

If the original component is damaged, compare several undamaged samples before recording the dimensions.

19. Production Trial Before Mass Manufacturing

Even when the dimensions appear correct, complete a trial assembly using:

Production hardware
Actual board material
Production drilling equipment
Intended edge banding or surface finish
Normal assembly tools

Check whether:

The cam fits correctly
The bolt remains secure
The cam engages smoothly
The panels close without a gap
Panel edges align
The cam reaches the intended locked position
The board remains undamaged
The joint stays stable after handling

Production should not begin solely because individual component dimensions passed inspection.

20. Incoming Inspection Checklist

When furniture connectors arrive, inspect:

Cam diameter
Cam height
Bolt total length
Thread dimensions
Bolt-head geometry
Dowel diameter and length
Material and finish
Cam rotation
Cam-and-bolt engagement
Component quantity ratio
Packaging labels
Product code
Drawing revision

Keep different bolt lengths and cam heights physically separated in storage.

Visually similar components should have distinct labels or stock codes.

21. Information to Include in an RFQ

A furniture connector request for quotation should include:

Connector type
Cam diameter
Cam height
Bolt total length
Bolt working length
Thread type and dimensions
Bolt-head dimensions
Dowel dimensions
Panel thickness
Panel material
Drilling drawing
Furniture application
Material
Surface finish
Quantity in sets
Quantity of each component
Packing requirement
Approved sample or reference product
Required drawing revision

Avoid sending only a photograph with the description “15 mm three-in-one connector.”

Common Dimension Problems

Problem	Possible dimensional cause
Cam fits but does not tighten	Wrong internal profile or bolt-head position
Cam sits above the surface	Hole too shallow or cam too high
Cam sits too deeply	Hole too deep or incorrect cam height
Bolt misses the cam	Incorrect center distance
Panels cannot close	Bolt working length too long
Cam turns without engaging	Bolt working length too short
Bolt becomes loose	Incorrect thread or pilot-hole diameter
Dowel cannot enter	Wrong dowel diameter or hole alignment
Panel cracks near the cam	Unsuitable hole position, depth or panel thickness
Replacement looks correct but fails	Same diameter but incompatible geometry

Frequently Asked Questions

What does a 15 mm furniture cam mean?

It normally refers to the nominal outside diameter of the cam housing or its drilling family. It does not define cam height, bolt compatibility or drilling position.

Are all 15 mm furniture cams interchangeable?

No. Their heights, internal profiles, bolt requirements, drilling depths and engagement positions may differ.

Is cam height the same as hole depth?

Not necessarily. The correct hole depth depends on the connector design and specified installation position.

How is furniture connector bolt length measured?

The supplier’s drawing should define the measurement points. Total length, thread length and installed working length should be recorded separately.

Why does the cam turn without catching the bolt?

The bolt may be installed too deeply, the centerlines may be misaligned, or the cam and bolt may be incompatible.

Why is there a gap between the furniture panels?

Possible causes include excessive bolt working length, an incorrectly installed dowel, wrong drilling depth or incomplete cam engagement.

Can I identify a connector from a photograph?

A photograph may help narrow the options, but measurements and an approved sample are normally needed to confirm compatibility.

What dimensions should I send to a supplier?

Send the cam diameter and height, bolt dimensions, thread specification, head geometry, dowel dimensions, panel thickness and complete drilling pattern.